Five-Minute Mechanosynthesis of Hypercrosslinked Microporous Polymers

Abstract

Designable porous materials have potential in a plethora of applications, but synthesis costs and strict reaction conditions limit their true commercialization. Herein, we show that hypercrosslinked polymers (HCPs) can be synthesized within minutes in a green, low-cost, mechanochemical route which avoids the use of traditional toxic solvents. Microporous HCPs were obtained in as little as 10 s, with optimum surface areas up to 782 m2 g–1 obtained in only 5 min and in quantitative yields for both Friedel–Crafts “knitting” and Scholl-coupling (SC) reactions. Liquid-assisted grinding of the SC model system resulted in higher porosity than the traditional solution-synthesized equivalent. ssNMR studies showed that a higher degree of polymerization was obtained from mechanosynthesis with the presence of a trace green solvent as a porogen resulting in such high porosity. This method allows a near limitless variety of highly porous polymers to be synthesized from an aromatic molecule within minutes.